vertical.pyΒΆ

# A rectangle grid with a vertical interface

name = "vertical.msh"
h = 0.1
hf = 0.1

import gmsh
gmsh.initialize()
gmsh.option.setNumber("General.Verbosity", 0)
gmsh.option.setNumber("Mesh.MshFileVersion", 2.2)

gmsh.model.add(name)

p1 = gmsh.model.geo.addPoint(   0, 0, 0, h, 1)
p2 = gmsh.model.geo.addPoint( 0.5, 0, 0, hf, 2)
p3 = gmsh.model.geo.addPoint(   1, 0, 0, h, 3)
p4 = gmsh.model.geo.addPoint(   1, 1, 0, h, 4)
p5 = gmsh.model.geo.addPoint( 0.5, 1, 0, hf, 5)
p6 = gmsh.model.geo.addPoint(   0, 1, 0, h, 6)

l1 = gmsh.model.geo.addLine(p1, p2, 1)
l2 = gmsh.model.geo.addLine(p2, p3, 2)
l3 = gmsh.model.geo.addLine(p3, p4, 3)
l4 = gmsh.model.geo.addLine(p4, p5, 4)
l5 = gmsh.model.geo.addLine(p5, p6, 5)
l6 = gmsh.model.geo.addLine(p6, p1, 6)
lf = gmsh.model.geo.addLine(p2, p5, 10)

gmsh.model.geo.addCurveLoop([1, 10, 5, 6], 1)
gmsh.model.geo.addPlaneSurface([1], 0)
gmsh.model.geo.addCurveLoop([2, 3, 4, -10], 2)
gmsh.model.geo.addPlaneSurface([2], 1)

gmsh.model.geo.synchronize()

gmsh.model.mesh.generate(dim=2)
gmsh.write(name)
gmsh.finalize()

Figure made with TikZ

vertical.msh